A malaria model tested in the African savannah
Abstract
A new mathematical model of malaria has been developed for comparing the effects of alternative control measures. It describes both the temporal changes of the P. falciparum infection rate and the immunity level of the population as a function of the dynamics and characteristics of the vector populations, which are summarized in the concept of vectorial capacity. A critical vectorial capacity is specified, below which malaria cannot maintain itself at an endemic level. The model has been tested with epidemiological data collected in a WHO research project in the African Savannah, Kano State, Northern Nigeria, since October 1970. The estimates of the model parameters were obtained by minimizing the chi(2) function that measures the discrepancy between the observed and expected age-specific parasite rates in the two villages with the highest and the lowest vectorial capacity, respectively, at five surveys during one year of baseline data collection and between the observed and expected infant inoculation rates, in the main transmission seasons, in the same two villages. The model describes three aspects of immunity: loss of infectivity, loss of detectability, and increase of recovery rate. It is assumed that loss of infectivity precedes loss of detectability and increase of recovery rate. Superinfections are slowing down the recovery for high inoculation rates but do not reduce them to zero. They do not increase infectivity.
Similar articles
-
Further epidemiological evaluation of a malaria model.Bull World Health Organ. 1978;56(4):565-71. Bull World Health Organ. 1978. PMID: 365384 Free PMC article.
-
[Malaria transmission in 1999 in the rice field area of the Kou Valley (Bama), (Burkina Faso)].Sante. 2003 Jan-Mar;13(1):55-60. Sante. 2003. PMID: 12925325 French.
-
[Epidemiology of malaria in a village of Sudanese savannah area in Mali (Bancoumana). 2. Entomo-parasitological and clinical study ].Bull Soc Pathol Exot. 2003 Nov;96(4):308-12. Bull Soc Pathol Exot. 2003. PMID: 14717049 French.
-
[Current malaria situation in the Republic of Kazakhstan].Med Parazitol (Mosk). 2001 Jan-Mar;(1):24-33. Med Parazitol (Mosk). 2001. PMID: 11548308 Russian.
-
Malaria and mortality: some epidemiological considerations.Ann Trop Med Parasitol. 1997 Oct;91(7):811-25. doi: 10.1080/00034989760572. Ann Trop Med Parasitol. 1997. PMID: 9625938 Review.
Cited by
-
Estimating the burden of malaria in Senegal: Bayesian zero-inflated binomial geostatistical modeling of the MIS 2008 data.PLoS One. 2012;7(3):e32625. doi: 10.1371/journal.pone.0032625. Epub 2012 Mar 5. PLoS One. 2012. PMID: 22403684 Free PMC article.
-
Vector capacity of Anopheles sinensis in malaria outbreak areas of central China.Parasit Vectors. 2012 Jul 9;5:136. doi: 10.1186/1756-3305-5-136. Parasit Vectors. 2012. PMID: 22776520 Free PMC article.
-
Anopheles mortality is both age- and Plasmodium-density dependent: implications for malaria transmission.Malar J. 2009 Oct 12;8:228. doi: 10.1186/1475-2875-8-228. Malar J. 2009. PMID: 19822012 Free PMC article.
-
Malaria and its possible control on the island of Príncipe.Malar J. 2003 Jun 18;2:15. doi: 10.1186/1475-2875-2-15. Epub 2003 Jun 18. Malar J. 2003. PMID: 12875660 Free PMC article.
-
A simplified model for predicting malaria entomologic inoculation rates based on entomologic and parasitologic parameters relevant to control.Am J Trop Med Hyg. 2000 May;62(5):535-44. doi: 10.4269/ajtmh.2000.62.535. Am J Trop Med Hyg. 2000. PMID: 11289661 Free PMC article.
References
-
- Trop Dis Bull. 1950 Oct;47(10):907-15 - PubMed
MeSH terms
LinkOut - more resources
Full Text Sources